Matching Items (45)
Description
Haiti has witnessed high deforestation rates in recent decades, caused largely by the fuel needs of a growing population. The resulting soil loss is estimated to have contributed towards a decline in agricultural productivity of 0.5% -1.2% per year since 1997. Recent studies show the potential of biochar use through pyrolysis technology to increase crop yields and improve soil health. However, the appropriateness of this technology in the context of Haiti remains unexplored. The three objectives of this research were to identify agricultural- and fuel-use-related needs and gaps in rural Haitian communities; determine the appropriateness of biochar pyrolyzer technology, used to convert agricultural biomass into a carbon-rich charcoal; and develop an action-oriented plan for use by development organizations, communities, and governmental institutions to increase the likelihood of adoption. Data were collected using participatory rural appraisal techniques involving 30 individual interviews and three focus-group discussions in the villages of Cinquantin and La Boule in the La Coupe region of central Haiti. Topics discussed include agricultural practices and assets, fuel use and needs, technology use and adoption, and social management practices. The Sustainable Livelihoods framework was used to examine the assets of households and the livelihood strategies being employed. Individual and focus group interviews were analyzed to identify specific needs and gaps. E.M. Rogers' Diffusion of Innovations theory was used to develop potential strategies for the introduction of pyrolysis technology. Preliminary results indicate biochar pyrolysis has potential to address agricultural and fuel needs in rural Haiti. Probable early adopters of biochar technology include households that have adopted new agricultural techniques in the past, and those with livestock. Education about biochar, and a variety of pyrolysis technology options from which villagers may select, are important factors in successful adoption of biochar use. A grain mill as an example in one of the study villages provides a model of ownership and use of pyrolysis technology that may increase its likelihood of successful adoption. Additionally, women represent a group that may be well suited to control a new local biochar enterprise, potentially benefiting the community.
ContributorsDelaney, Michael Ryan (Author) / Aggarwal, Rimjhim (Thesis advisor) / Chhetri, Nalini (Committee member) / Henderson, Mark (Committee member) / Arizona State University (Publisher)
Created2011
Descriptionnone
ContributorsZamil, Ruaa (Author) / Parmentier, Mary J (Thesis advisor) / Chhetri, Nalini (Committee member) / Grossman, Gary (Committee member) / Arizona State University (Publisher)
Created2013
Description
Growing concerns over climate change and the lack of a federal climate policy have prompted many sub-national organizations to undertake greenhouse gas (GHG) mitigation actions on their own. However, the interventions associated with these efforts are typically selected in a top-down and ad hoc manner, and have not created the desired GHG emissions reductions. Accordingly, new approaches are needed to identify, select, develop, and coordinate effective climate change mitigation interventions in local and regional contexts. This thesis develops a process to create a governance system for negotiating local and regional climate interventions. The process consists of four phases: 1) mapping the overall transition, 2) reconstructing the current intervention selection system, 3) assessing the system against principles identified in the literature, and 4) creating an improved system based on the assessment. This process gives users a detailed understanding of how the overall transition has progressed, how and why interventions are currently selected, what changes are needed to improve the selection system, and how to re-structure the system to create more desirable outcomes. The process results in an improved system that relies on participation, coordination, and accountability to proactively select evidence-based interventions that incorporate the interests of stakeholders and achieve system-level goals. The process was applied to climate change mitigation efforts underway in Sonoma County, California to explore the implications of real-world application, and demonstrate its utility for current climate change mitigation efforts. Note that results and analysis from interviews with Sonoma County climate actors are included as a supplementary file.
ContributorsCulotta, Daniel Scott (Author) / Wiek, Arnim (Thesis advisor) / Basile, George (Committee member) / Shrestha, Milan (Committee member) / Arizona State University (Publisher)
Created2012
Description
A niche group of non-traditional sports have grown in popularity over the course of most of the last century but especially in the last few decades. Adventure sports provide alternative forms of physical activity typically involving elements of nature, speed, adrenaline, and physical risk. These sports often take place in remote locations, require specialized equipment, and receive limited exposure to those that are not participants. There are many factors that contribute to limited participation within adventure sports but their popularity has continued to grow. Participants frequently devote much of their time, effort, and money showing a true passion for their sport. A case study on water skiers was performed to learn more about adventure sports and their participants. A detailed description of competitive water skiing is included because the competition format is not widely known. It was found that there are a number of reasons why people competitively water ski. The main ones are the unique sensations it offers, the water ski community, and the environment in which it takes place. It is a tough sport to become involved because of the costs, time commitments, access to lakes, and lack of knowledgeable skiers willing to mentor beginners. Although for different reasons, all respondents seemed to truly love the sport. People participate in adventure sports because of the unique aspects and opportunities involved with sports of this nature. The second portion is a coaching guide on all three events, driving, and judging including video examples of all but very high difficulty tricks. These tips and advice have been derived from fifteen years of experience with competitive water skiing. There is no single way to water ski but this is what one skier has found to help at each stage of improvement. It could not have been accomplished without the unimaginable amount of support received from family, coaches, and friends. It is always better to be watched by a coach but that is not always possible. This guide will give skiers a starting point for what to think about to help them figure out how to continue to improve in all three events. With the necessary time, resources, ambition, and circumstances; a small group of people who know nothing about water skiing could learn to become high performance competitors. It will be left with Sun Devil Water Ski Club to help future skiers who do not always have another skier to help teach them.
ContributorsMechler, Mason Charles (Author) / Chhetri, Nalini (Thesis director) / Yesenski, Tara (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / Chemical Engineering Program (Contributor)
Created2015-05
Description
This paper was born of the researcher's personal interest. As someone who commutes by bike and plans to continue to do so for the foreseeable future, the researcher was intrigued by the growing bicycle culture in Phoenix, Arizona, a city that can sometimes make commuting without a car quite difficult. The researcher aimed to uncover why cycling is becoming more popular as a mode of transportation in a city that can often be hostile towards cyclists. This paper first reviews some previous studies done on alternative commuting. Next, it details a commute-shed analysis conducted with the help of the US Census Bureau's On The Map program. After that, the researcher describes the methods used to gather qualitative data about attitudes from local commuters and discusses the results. Finally, suggestions and speculations are made about ways to improve the bikeability of the Phoenix metropolitan area. The research found that cyclists in the area are motivated to commute by bike by factors including cost-savings, health benefits, and others. This data is important because it shows that the target demographic, who are able to exert their desires politically, feel strongly enough about commuting by bicycle to go out of their way to do it.
ContributorsParma, Alexander John (Author) / Kelley, Jason (Thesis director) / Shrestha, Milan (Committee member) / Valandra, Patrick (Committee member) / Barrett, The Honors College (Contributor) / Department of Supply Chain Management (Contributor) / School of Sustainability (Contributor)
Created2014-05
Description
An investigation is undertaken of a prototype building-integrated solar photovoltaic-powered thermal storage system and air conditioning unit. The study verifies previous thermodynamic and economic conclusions and provides a more thorough analysis. A parameterized model was created for optimization of the system under various conditions. The model was used to evaluate energy and cost savings to determine viability of the system in several circumstances, such as a residence in Phoenix with typical cooling demand. The proposed design involves a modified chest freezer as a thermal storage tank with coils acting as the evaporator for the refrigeration cycle. Surrounding the coils, the tank contains small containers of water for high-density energy storage submerged in a low freezing-point solution of propylene glycol. The cooling power of excess photovoltaic and off-peak grid power that is generated by the air conditioning compressor is stored in the thermal storage tank by freezing the pure water. It is extracted by pumping the glycol across the ice containers and into an air handler to cool the building. Featured results of the modeling include the determination of an optimized system for a super-peak rate plan, grid-connected Phoenix house that has a 4-ton cooling load and requires a corresponding new air conditioner at 4.5 kW of power draw. Optimized for the highest payback over a ten year period, the system should consist of a thermal storage tank containing 454 liters (120 gallons) of water, a 3-ton rated air conditioning unit, requiring 2.7 kW, which is smaller than conventionally needed, and no solar photovoltaic array. The monthly summer savings would be $45.The upfront cost would be $5489, compared to a conventional system upfront cost of $5400, for a payback period of 0.33 years. Over ten years, this system will provide $2600 of savings. To optimize the system for the highest savings over a twenty year period, a thermal storage tank containing 272 liters (72 gallons) of water, a 40-m2 photovoltaic array with 15% efficiency, and a 3.5-ton, 3.1-kW rated air conditioning unit should be installed for an upfront cost of $19,900. This would provide monthly summer savings of $225 and 1062 kWh grid electricity, with a payback period of only 11 years and a total cost savings of $12,300 over twenty years. In comparison, a system with the same size photovoltaic array but without storage would result in a payback period of 16 years. Results are also determined for other cooling requirements and installation sizes, such that the viability of this type of system in different conditions can be discussed. The use of this model for determining the optimized system configuration given different constraints is also described.
ContributorsMagerman, Beth Francine (Author) / Phelan, Patrick (Thesis director) / Goodnick, Stephen (Committee member) / Chhetri, Nalini (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2013-05
Description
The City of Phoenix (Arizona, USA) developed a Tree and Shade Master Plan and a Cool Roofs initiative to ameliorate extreme heat during the summer months in their arid city. This study investigates the impact of the City's heat mitigation strategies on daytime microclimate for a pre-monsoon summer day under current climate conditions and two climate change scenarios. We assessed the cooling effect of trees and cool roofs in a Phoenix residential neighborhood using the microclimate model ENVI-met. First, using xeric landscaping as a base, we created eight tree planting scenarios (from 0% canopy cover to 30% canopy cover) for the neighborhood to characterize the relationship between canopy cover and daytime cooling benefit of trees. In a second set of simulations, we ran ENVI-met for nine combined tree planting and landscaping scenarios (mesic, oasis, and xeric) with regular roofs and cool roofs under current climate conditions and two climate change projections. For each of the 54 scenarios, we compared average neighborhood mid-afternoon air temperatures and assessed the benefits of each heat mitigation measure under current and projected climate conditions. Findings suggest that the relationship between percent canopy cover and air temperature reduction is linear, with 0.14 °C cooling per percent increase in tree cover for the neighborhood under investigation. An increase in tree canopy cover from the current 10% to a targeted 25% resulted in an average daytime cooling benefit of up to 2.0 °C in residential neighborhoods at the local scale. Cool roofs reduced neighborhood air temperatures by 0.3 °C when implemented on residential homes. The results from this city-specific mitigation project will inform messaging campaigns aimed at engaging the city decision makers, industry, and the public in the green building and urban forestry initiatives.
ContributorsMiddel, Ariane (Author) / Chhetri, Nalini (Author) / Quay, Raymond (Author)
Created2015
Description
Shade plays an important role in designing pedestrian-friendly outdoor spaces in hot desert cities. This study investigates the impact of photovoltaic canopy shade and tree shade on thermal comfort through meteorological observations and field surveys at a pedestrian mall on Arizona State University’s Tempe campus. During the course of 1 year, on selected clear calm days representative of each season, we conducted hourly meteorological transects from 7:00 a.m. to 6:00 p.m. and surveyed 1284 people about their thermal perception, comfort, and preferences. Shade lowered thermal sensation votes by approximately 1 point on a semantic differential 9-point scale, increasing thermal comfort in all seasons except winter. Shade type (tree or solar canopy) did not significantly impact perceived comfort, suggesting that artificial and natural shades are equally efficient in hot dry climates. Globe temperature explained 51 % of the variance in thermal sensation votes and was the only statistically significant meteorological predictor. Important non-meteorological factors included adaptation, thermal comfort vote, thermal preference, gender, season, and time of day. A regression of subjective thermal sensation on physiological equivalent temperature yielded a neutral temperature of 28.6 °C. The acceptable comfort range was 19.1 °C–38.1 °C with a preferred temperature of 20.8 °C. Respondents exposed to above neutral temperature felt more comfortable if they had been in air-conditioning 5 min prior to the survey, indicating a lagged response to outdoor conditions. Our study highlights the importance of active solar access management in hot urban areas to reduce thermal stress.
ContributorsMiddel, Ariane (Author) / Selover, Nancy (Author) / Hagen, Bjorn (Author) / Chhetri, Nalini (Author)
Created2016-05-18
Description
Stormwater run-off control is emerging as one of the key sustainability challenges for the cities around the world, especially the coastal and flood-prone cities. Sustainable management of stormwater run-off is important because urban infrastructures (e.g., buildings, roads, and parking) effectively seal the land surface and disrupt the natural hydrological cycle, often disproportionately burdening the poor and disfranchised communities inhabiting the flood zones. The devastating results of flooding have pushed urban designers to actively consider "green infrastructure" as a more effective option to mitigate flooding risks and to enhance urban resilience. Green infrastructure connects nature-based solutions to effectively manage stormwater run-offs and provides several social, economic, and environmental benefits. Focusing on the use and governance of green infrastructure, this study addresses two key research questions: What are the ways green infrastructure helps urban stormwater management and overall urban sustainability in the developing countries? What are the challenges Lantin American cities face in comparison to the cities in the developed countries? This study applies a case study analysis approach to compare three Latin American cities: 1) Bogota (Columbia), Curitiba (Brazil), and Santiago (Chile), as those are representative of rapid urbanization trends occurring in the developing countries, and they have already green infrastructure in their urban design. The results of this study suggest that green infrastructure has significant benefits for the cities in developing countries, but it is also important to focus on the governance aspects that allow for a city to properly implement green infrastructure and create more adaptive and resilient cities.
ContributorsVillalobos, Vanessa (Author) / Shrestha, Milan (Thesis director) / Hagen, Bjoern (Committee member) / School of Sustainability (Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Campus sustainability and the goal of reaching carbon neutrality have become a major trend among many Higher Education Institutions (HEIs) globally, and many of them have taken public pledges to reach carbon neutrality as early as 2025. Despite this push and apparent eagerness to make campuses greener, the simple fact remains that HEIs account for very little of the global carbon footprint, and achieving carbon neutrality does very little to combat climate change in the grand scheme of things. It is widely held that HEIs seek to use carbon neutrality goals to demonstrate their strong commitment to sustainability and also to educate the next generation of thinkers and leaders in the hopes that graduates from these institutions apply these methods to higher levels of society thereby decarbonizing communities’ level by level. However, since carbon neutrality took center stage in campus sustainability goals, it is imperative to scrutinize and audit the past and current energy portfolio and analyze any meaningful changes to see their year-by-year progress and what methods have been most successful in reaching carbon neutrality. Not only that, but carbon neutrality seemingly means different things to different institutions. This research asks what is the role of a campus energy portfolio in terms of achieving carbon neutrality? Using the Institutional Analysis and Development framework, this research utilizes a case study analysis of Arizona State University which was one of the first universities in the United States to achieve carbon neutrality. The results of this study suggest that a campus energy portfolio is integral in understanding the role of carbon neutrality and that becoming carbon neutral is not always the “green standard” indicator many HEIs want others to think it is.
ContributorsSingh, Sukhmani Kaur (Author) / Shrestha, Milan (Thesis director) / Parker, Nathan (Committee member) / School of Politics and Global Studies (Contributor) / School of International Letters and Cultures (Contributor) / School of Sustainability (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-12